1. Field of the Invention
The present invention relates generally to data visualization and in particular to methods for representing data in a pie chart.
2. Description of Related Art
Data visualization software has become one of the most competitive segments of the software industry. The primary goal of data visualization software is to represent data to a user in a convenient, effective and meaningful way. Typically, pie charts, bar charts, line charts, and area charts are the most widely used graphical representations. It is important to ensure that these graphical representations convey as much information about the underlying data as possible and be aesthetically pleasing.
In the case of pie charts, information in the form of labels is generally shown outside the pie slices when there are many small data elements. Association of a label with a corresponding slice is shown by a connecting line drawn between them. However, there are many challenges when small slices are concentrated at one place
Sometimes, the data provided by the smaller elements in a pie chart are equally important or even more important than other elements. For example, there may be 20 elements, where 3 of the elements comprise 80 percent of the total area of the chart, while the remaining 17 elements are shown as very small slices. In this case, it is very difficult to show all the labels with connecting lines to their slices at once using a typical layout. Hence, there is a strong need to show such kind of information in pie charts in a satisfactory layout.